TW396087B - Laping tape - Google Patents

Abstract

This is a lapping tape with a lapping layer on a flexible substrate. It has inorganic powders and a binder as main components. The binder contained in the lapping layer has (1) a phenoxy resin, and (2) a polyester polyurethane resin with a number-average molecular weight Mn not less than 20000 but not greater than 100000. Accordingly, the obtained lapping tape exhibits excellent prevention of lapping scratches generation on the surface to be lapped. The lapping layer peeling from the lapping tape can be suppressed; the lapping tape has excellent lapping ability.

Description

A 7 B7 V. Description of the invention (I) The present invention relates to honing belts for surface honing of magnetic heads, magnetic disks, etc. In the prior art, the precision processing of magnetic heads and the processing of the surface of magnetic recording media are on A honing belt with a honing layer is used on the flexible support. The honing layer is formed by applying a coating for forming a honing layer on a flexible support and drying it. The coating for forming a honing layer contains alumina, chromium oxide, silicon carbide, iron oxide, and silicon nitride. 2. Inorganic powder of gangue f; organic binders (adhesives) such as vinyl chloride resins, polyester resins, polyurethane resins, etc .; and other compounding agents such as kneaded and dispersed state. A known method for manufacturing i honing belts in the prior art is a method described in Japanese Patent Application Laid-Open No. 5 -1 9 2 8 6 9 which uses an average molecular weight of a repeating unit composed of a specific structural formula 1 0 0 0 ~ A method for manufacturing a honing belt after using an epoxy resin of 1 0 0 0 0, a coating containing a polyfunctional isocyanate, and a polyurethane resin having a number average molecular weight of 5 0 0 to 2 0 0 0 at the end. In this manufacturing method, after using the above-mentioned resins in combination, the crosslinking reaction speed can be sufficiently obtained even if the crosslinking reaction temperature is lowered to room temperature, and has a high crosslinking density. Printed by the Consumer Cooperatives of the Central Bureau of Standards of the Ministry of Economic Affairs -----.--- C ... equipment ΙΓ-'· (Please read the notes on the back before filling: ¾ this page) Also, JP 5-1 No. 9 2 8 7 0 discloses an average molecular weight of 1 0 0 0 to 5 0 0 0 0 and an average molecular weight of 1 0 0 0 to 3 0 0 0. Polyester resin with a glass transition point (Tg) at the end of 0 of OH group of _20 ° C ~ 40 ° C and a method for manufacturing a honing belt for a coating containing a polyfunctional isocyanate. After using this resin, it can reduce the uneven quality in the reaction hardening. It is reported that the paper size is applicable to the Chinese National Standard (CNS) A4 specification (210X297 mm). 4-Consumption by employees of the Central Standards Bureau of the Ministry of Economic Affairs Cooperative printed A7 _ B7 V. Description of the invention g) However, in any of these proposals, there is no sufficient coating film strength as a honing belt. In the honing test, the coating film of the honing layer did not appear. The falling pole is not ideal. The present invention aims at this unsatisfactory point when honing magnetic heads, magnetic discs and other surfaces... ---, a well-balanced enough honing belt can be used as a honing belt. The purpose of hairpin is to provide those who can completely prevent the honing and scratching on the surface of the honing object, and have sufficient coating film strength to reduce the honing layer of the honing belt while providing excellent honing functions. The honing belt. In order to solve the problem of the present invention, the present inventor made a precise discussion on the bonding composition that can be used in the honing belt, and found that after using the binder containing a mixture of a phenoxy resin and a polyester polyurethane resin of a specific molecular weight , Can effectively solve this problem, and then complete the present invention. That is, in the present invention, a honing belt with a honing layer containing inorganic powder and a binder as a main component is used on a flexible support. The binder containing the honing layer is composed of 1 ) A phenoxy resin and 2) a polyester polyurethane resin having a number-average molecular weight M n of 20,000 $ M n S 10,000. In addition, a preferred aspect of the present invention is one in which the number average molecular weight of the phenoxy resin is 100 000 or more ^. In a preferred embodiment of the present invention, the number-average molecular weight of the phenoxy resin is 100 to 300. In addition, the present invention is intended to be formed by a weight ratio of a phenoxy resin to a polyester polyurethane resin of 5: 9 5 to 7 0 3 Q.

V In addition, the ideal form of the present invention is that the glass transition temperature scale of polyester polyurethane is applicable to the Chinese National Standard (CNS) A4 specification (210X297 mm) _ c-(Please read the precautions on the back before filling in {:? (This page)

Printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs A 7 · B7 · V. Description of the invention 0) Degree T g is composed of 50 ° C ~ 80 ° C. In addition, an ideal form of the present invention is one in which the inorganic powder has a Mohs hardness of 5 or more and a particle size of 0.1 to 20 # m. In addition, an ideal form of the present invention is a composition of the honing belt of the present invention used for a honing head of a magnetic head or a magnetic disk. Brief Description of Drawings Fig. 1 is a schematic sectional view of a honing belt according to the present invention. .... Hereinafter, an ideal embodiment of the present invention will be described in detail with reference to FIG. 1. FIG. 1 is a schematic sectional view showing an embodiment of the honing belt of the present invention. The honing belt 1 of the present invention is attached to a flexible support 2 and is a surface provided by a honing magnetic head ', magnetic-disc-disc, etc. (hereinafter referred to as "__ 被' 硏 stomach -_" _) _磨. Layer 3. The honing layer 3 contains an inorganic powder of a honing material and a binder for bonding the inorganic powder. i '. The honing layer 3 of the present invention is a honing mixture in which the inorganic powder is mixed with a binder (and various organic solvents) and other (organic) solvents if necessary, and the coating is formed on a flexible support. After 2 times, it is dried and formed. In the present invention, a phenoxy resin is used in the binder, and the number average molecule is

-· Polyurethane resin with S amount Mn of 200 0 OSMnSi 000 0 0 is contained as an essential component. The phenoxy resin used in the present invention is a nested molecular weight polyhydroxy polyether synthesized from bisphenol A and epichlorohydrin. The chemical structure is the same as that of epoxy resin, but it is compared with the epoxy resin generally used. Tree hire, its molecular weight is extremely large. . '一 I In —m —Mt n I4H nn · — nt ^^' Please read the two notes before you fill in this page). This paper size applies the Chinese National Standard (CNS) A4 specification (2) 〇x29Tifrt ), g_ A7 B7 V. Description of the invention f) And the number average molecular weight M η of the phenoxy resin used in the present invention is more than 10,000, especially those with 10,000 or more and 30,000 or less are ideally applicable. If a general epoxy resin is used, its number average molecular weight is 100 or less, and the strength of the coating film cannot be fully obtained, and problems such as peeling of the coating film of the honing layer are likely to occur. Among them, the average molecular weight is measured by a so-called standard polystyrene method. The phenoxy resin is a content of 5 to 70% by weight of the total amount of the binder, preferably 10 to 60% by weight, and more preferably 10 to 50% by weight. When the content is less than 5% by weight, the coating film strength of the honing layer will decrease, and problems such as peeling of the coating film of the honing layer will appear. On the other hand, if the content is more than 70% by weight, the coating film of the honing layer becomes hard and brittle and has no softness, causing the cause of damage to the honing material. Specific examples of the phenoxy group used in the present invention are, for example, Phenoxy 8 5500;-65 phenoxy resin company's "? Rule 11 (:", "PKHH", "PKHJ" and so on. These all meet The range of the above-mentioned ideal number average molecular weight. I Printed by the consumer cooperation of the Central Bureau of Standards of the Ministry of Economic Affairs (please read the precautions on the back before filling this page). ^ The amount Mη is 20000SMnl00000, preferably a polyester polyurethane resin of 2000 OSMnS 8 0 0 0 as an essential component. A polyester polyurethane resin having the number average molecular weight Mη is contained in the honing layer. It can improve the dispersibility of the coating for forming the honing layer, so that the honing layer formed by the coating has excellent honing characteristics. '(X, the number average molecular weight of the polyester polyurethane resin Mη is less than 2 0 0 0 0 Μ, the size makes 硏Reduced coating strength of abrasive layer, film fall of honing layer, etc. This paper size applies Chinese National Standard (CNS) A4 specification (210X297 mm) -7- Printed by A7 B7, Consumer Cooperative of Central Standards Bureau, Ministry of Economic Affairs , Invention description households). If the average molecular weight Mη is greater than 10,000, the dispersion of the coating for forming the honing layer will be reduced, resulting in deterioration of the surface of the honing layer and causing damage to the honing material during the honing operation. Content of the polyester polyurethane resin 30% to 95% by weight, preferably 40% to 90% by weight, and more preferably 50% to 90% by weight of the adhesive. The polyester polyurethane resin content exceeds 95% by weight and then honed The strength of the coating film decreases, and the coating film of the honing layer falls off. Conversely, if the content is less than 30% by weight, the coating film of the honing layer becomes hard and brittle and has no softness. It is easy to cause honing during honing In addition, the glass transition temperature T g of the polyester polyurethane resin is -50. (: STgS80 ° C, preferably -5p ° CSTgS + 4〇t :, more preferably -4 5 ° CSTgS +2 0t range. 1. When the glass transition temperature is too low, the strength of the honing layer coating film is reduced, and the honing capacity is reduced. On the other hand, if the glass transition temperature T g is too high, the honing layer coating film is hard and brittle, showing no The state of softness causes damage to the object to be honed during honing operation. In addition, the glass transfer of this resin is 1 degree T g based on値 measured by a dynamic viscoelasticity measuring device. The polyester polyurethane resin used in the present invention is a compound obtained by reacting a polyester diol with an isocyanate and a desired chain extender. The polyester used in the present invention Polyurethane resins are those that react organic diisocyanate (A), polyester diol (B) with a molecular weight of 500 to 50,000, and a chain extender ((:) with a molecular weight of 500 or less. Polyester polyurethane ^ Diisocyanate (»A) used in the resin manufacturing, for example: 2,4-toluene diisocyanate, 2,6-toluene This paper size is applicable to Chinese national standards (CNS > A4 specifications (210X 297 mm) _ ft-'：-_____________ D *. T {Please read the note t on the back and fill in & this page) · Printed by the Shellfish Consumer Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs A7 B7 V. Description of the invention-) Brewing monoisocyanate, p-phenylene diisocyanate, diphenylmethyl diisocyanate, m-phenylene diisocyanate, hexamethylene diisocyanate, tetramethylene monoisocyanate, 3 '3 —dimethoxy-4,4-—bisfluorene diisocyanate, 2,4- Diisocyanate, 3,3-Dimethyl-1 4 '4 / monobisene diisocyanate, -4,4 < monodiene diisocyanate, 4,4 / --diisocyanate diphenyl ether, 1,5 —Naphthalene diisocyanate, p-xylene diisocyanate, m-xylene diisocyanate '1' 3-diisocyanate methylcyclohexane, 1,4-diisocyanate methylcyclohexane, 4, 4 / Examples of diisocyanate cyclohexane, 4,4-- diisocyanate cyclohexanemethane, isoflurone diisocyanate, and the like. Examples of the polyester diol (B) used in the production of the polyester polyurethane resin are those having a molecular weight in the range of 500 to 50,000. Examples of the carboxylic acid components of polyester diols are: aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, phthalic acid '1' 5-naphthalenedicarboxylic acid, p-oxybenzoic acid, p-- Examples of aromatic oxycarboxylic acids such as (hydroxyethoxy) benzoic acid; aliphatic dicarboxylic acids such as succinic acid, adipic acid, azelaic acid, sebacic acid, and lauric acid. Among them, terephthalic acid, isophthalic acid, phthalic acid, 'adipic acid, and sebacic acid are particularly preferable. In addition, the glycol component of polyester diol is, for example, ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl Diethylene glycol, diethylene glycol, dipropylene glycol, 2,2,4-trimethyl-1, .. 3-pentanediol, cyclohexanedimethanol, bisphenol A ethylene oxide additives and propylene oxide Additives, hydrogenated bisphenol A ethylene oxide additives and propylene oxide additives, etc. This paper size applies Chinese National Standard (CNS) A4 specification (210X 297 mm) -9-(谙 Read the precautions on the back before filling in this page) Binding · Ordering A7 B7 Printed by the Staff Consumer Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs 、 Instructions of the invention P.) 1 1 Other examples of this polyester diol: δ — Caprolactones such as caprolactone after opening TSt bad 1 1 | Examples of lactone polyester diols obtained after polymerization 〇1 1 The long-chain diol (B), as described above, is used to improve the mechanical properties of the polyester polyurethane resin. It is a polyester diol with a molecular weight of 5.0 0 5 5 0 0. It is recommended to use 1 1 if the molecular weight is less than 5 0 0 The concentration of the amine ester group is too high. The resin is soft in the back 6 1 I Properties > Solvent solubility is reduced to produce a bad situation. 0 Conversely, the molecular weight is too large to pay attention. Too low low-polyester polyurethane resin special feature 1 has strong toughness and wear resistance Unsatisfactory 0 Filling; the chain extender (C) with a molecular weight less than page 1 1 5 0 0 used in the manufacture of polyester polyurethane resin contains more than 2 active hydrogens in 1 molecule 1 1, S field m After the concentration of urethane group or urethane group in the polyester polyurethane resin is adjusted, a unique strong toughness effect is attached to the polyester 1 polyurethane. The specific compound of the chain extender (C) such as ethylene glycol, 1 3 1 1 I — propylene glycol, 1 4 — butanediol 1 6 — hexanediol> cyclohexanedimethyl 1 1 alcohol xylene glycol, diethylene glycol triethylene glycol, bisphenol A ethylene oxide 1 alkane addition Straight-chain diols such as propylene glycol & neopentyl glycol > 1 2 monobutyl- * | — alcohol 1 3 — butanediol% 2 2 4 — trimethyl-1 3 _ 1 I pentanediol, bis Branched diol monoethanol of phenol A propylene oxide addition 1 1 I Amine \ Amine alcohol such as n-methylethanolamine, ethyl Diamine% Hexamethylenediamine 1 > Diamines such as isoflurone diamine or hydrogen, etc. 0 1 1 Ideal for the polyester polyurethane resin of the present invention, such as polyester di 1 | alcohol (1 ) / Polyesterdiol (2) / neopentyl glycol / 4 4 diphenylbenzene 1 I The reaction product of the methyl isocyanate diisocyanate, the example of polyesterdiol (1) 1 1 I such as: terephthalene Formic acid / isophthalic acid / ethylene glycol / neopentyl glycol 1 1 This paper size applies to the Chinese National Standard (CNS) A4 format (210X297 mm) -10- Du Yinju A 7 B7 V. Explanation of the invention) 50/50/50/50 Morse ratio, for example, polyester diester (2): adipic acid / 1,4-butanediol / neopentylene glycol = 10.00 / 7 5/2 5 Morse. In addition, by controlling the blending ratio of the polyester diol (1) / polyester diol (2) and the concentration of the amine ester group, the glass transition temperature Tg of the polyester polyurethane resin can be arbitrarily controlled. The amount of the binder contained in the honing layer (coating material for forming a honing layer) is 5 to 50 parts by weight of 100 parts by weight of the inorganic powder contained in the honing layer, and particularly 10 to 40 weight. Sharers are good. When the content of the binder is less than 5 parts by weight, the strength of the coating film of the honing layer will be reduced, and the coating film of the honing layer will fall off. Conversely, if the content of the binder is more than 50 parts by weight, the content of the inorganic powder will be reduced, resulting in poor honing characteristics. As examples of the cross-linking agent for hardening the binder, various polyisocyanates, particularly diisocyanates, are preferably used with more than one tolyl diisocyanate, hexamethylene diisocyanate, and methylene diisocyanate. . This cross-linking agent is preferably a cross-linking agent denatured with a plurality of hydroxyl groups such as trimethylolpropane or a triisocyanate-type cross-linking agent in which three molecules of a diisocyanate compound are combined. The cross-linking agent is a resin cross-linked with a functional group or the like contained in the adhesive. The content of the crosslinking agent is preferably 10 to 30 parts by weight based on 100 parts by weight of the binding agent. Hardening heat The hardening resin is usually heated in a heating oven at 40 to 80 ° C for 1 to 4 to 8 hours. As an inorganic powder contained as a necessary component in the coating for forming the honing layer (honing layer), users with a Mohs hardness of 5 or higher are advised to use it. 'For example: carbonized paper standards are applicable to China National Standard (CNS) A4 specifications ( 210X297mm) -11-~ ", two Γ m ml 1V1 I tm · —1 ^ —fv I t ， T-(Please read the precautions on the back before filling the 1ΪΤ page) A7 ______ B7 V. Description of the invention $ ) Fine powders of silicon, aluminum oxide, silicon nitride, chromium oxide, chromium oxide, diamond, emery, etc. are used alone or in combination of two or more types. Among them, silicon carbide or alumina users are more ideal. The particle size of the inorganic powder is preferably 0.1 ~ 2 0 Am, and the specific particle size that is practically supplied can be selected to be included in the actual rough scraping or processing honing purpose. If the particle size is less than 0.1 Am, the honing function will be insufficient for processing honing. Conversely, if it is larger than 20 / zm, the problem of damage to the honing object during rough scraping will occur. Also, in the honing layer of the present invention, as an additive, if necessary, the user has a lubricating effect, an antistatic effect, a dispersing effect, and a plasticizing effect. Specific examples include fatty acids, fatty acid esters, and silicone oils. , Fluorine oil, various surfactants, carbon black, etc. can be added. Printed by the Consumers 'Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs --- ^ ------'. One Pack ---'- (锖 Read the precautions on the back before filling this page) as a honing layer For organic solvents used in coatings, such as: ketones such as methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, aromatic hydrocarbon groups such as toluene and xylene, and esters such as ethyl acetate and butyl acetate Or use these mixed solvents at any ratio. Among them, those having a high boiling point solvent containing cyclohexanone are preferred because they can form a good honing layer. Cyclohexanone is contained in an amount of 20 to 60% by weight in the total organic solvent, more preferably 25 to 50% by weight. Within this range, good surface quality of the honing layer can be obtained, the honing function can be improved, and the occurrence of scratches on the honing layer can be prevented. The solid content concentration of the coating for forming the honing layer is preferably from 30 to 70% by weight, and more preferably from 40 to 60% by weight. If the ratio is less than 30% by weight, the honing layer is formed. The amount of residual solvent will increase, making it impossible to obtain a uniform coating film and other undesirable conditions. Conversely, if it is greater than 70% by weight, the size of the coated paper applies the Chinese National Standard (CNS) A4 specification (210X297 mm) -12 · Printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs A7 B7 V. Invention Description 彡 〇) The viscosity of the material increases, and the coating film of the honing layer dries too fast to obtain uniform sentences. The coating film is not ideal. The film thickness of the honing layer 3 is selected according to the shape and material of the object to be honed. Generally, it is 3 ~ 25 / zm, and more preferably 5 ~ 20em. If the film thickness is less than 3, the elasticity of the coating film will disappear because the film thickness is too thin. Honing operation is easy to damage and to be honed. Conversely, if it is too large beyond 2 5 # m, honing-scratches are likely to occur during honing operations. Honing layer 3-Generally, it can be formed by coating alone, or two or more layers. As the flexible support 2 used in the present invention, a film such as polyethylene terephthalate (PET), polyvinyl naphthalate (PEN), polyamide, polyimide, or the like can be used. If necessary, inorganic compounds such as oxides, carbonates, etc. of the fillers A1, Ca, Si, Ti, etc., organic compounds such as acrylic resin fine powder, and the like may be added. The film center is preferably P E T, PEN, or aromatic polyamidamine. More preferably, two or three layers of PET or PE N are laminated to form a composite film. The flexible support may be subjected to a corona discharge treatment, a plasma discharge and / or a polymerization treatment in advance, an easy adhesive coating treatment, a descaling treatment, a heat treatment and / or a damping treatment, and then a relaxation treatment. Generally, the thickness of the flexible support 2 is 5 to 100 mm. When manufacturing the coating for forming the honing layer of the present invention, the user of the dispersing machine is preferably a ball mill, a grinder, or a sand mixer. It is advisable to install a filtering process in the dispersed paint. If there are undispersed inorganic powders, aggregates, or resin-insoluble matter in the coating for forming the honing layer, the formation of the honing layer coating film may cause a loss and damage to the honing material. In addition, the filtration engineering is to remove ^ ϋ n ^ i nn I ^ n ^ i ml. ^ N ml, one OJ '-(谙 Please read the precautions on the back before filling this page) This paper size applies Chinese national standards (CNS ) A4 specification (2 丨 0X297 mm) -13- A7 B7 V. Description of the invention (η) The purpose is to remove the foreign matter in the coating for honing layer formation. When manufacturing honing belts, the non-magnetic support is continuously formed by rolling and rolling. When necessary, the hardener is mixed at the same time (or mixed). The coating is filtered by a filter with a certain filtration accuracy. Various coating methods such as gravure coating, reverse roll coating, and extrusion nozzle coating are used to coat the coating for forming a honing layer. Generally, the curved support 2 of the coating before coating is used for washing and surface adjustment purposes, wet washing with water, solvent, etc .; non-woven fabrics, ultra-fine fiber fabrics, etc. · dry washing for two brushes; squeezing air Various methods known in the art, such as non-contact washing such as vacuum, ionized air, etc., are used to perform the pretreatment of the flexible support. For the purpose of improving the adhesion between the paint and the flexible support, and the coating surface, various known non-contact surface treatments such as corona discharge, ultraviolet irradiation, and electron irradiation can be performed. 'Printed by the Consumers' Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs (read the precautions on the back and then fill out this page) The coating for forming the honing layer applied to the flexible support 2 is generally installed inside a drying furnace, etc. Far-infrared rays, electric heaters, vacuum devices, and other known drying and evaporation methods. The drying temperature is 40 ~ 200 ° C, more than 隹 60 ~ 180 ° C, more preferably 80 ~ 150 ° C. Depending on the heat resistance of the flexible support, the type of solvent, and the concentration of solid content, etc., it should be appropriately selected. When the drying temperature is less than 40 ° C, the drying efficiency decreases and the amount of residual solvent increases. On the other hand, when it exceeds 200 ° C, the solvent in the honing layer coating film evaporates rapidly, resulting in deterioration of the surface roughness of the honing layer. In addition, the temperature in the drying furnace can also be matched. Generally, the gas in the drying furnace can be air or inactivated gas. After drying the honing layer 3, in order to promote the hardening of the honing layer, the Chinese paper standard (CNS > A4 (210X297 mm)) can be applied to this paper size. 14-A7 B7 V. Description of the invention (12) 4 0 ° C ~ 80 ° C heat curing treatment and / or mold line irradiation treatment. After the cutting process of the predetermined shape is performed, the secondary processing is performed to make the honing belt of the present invention. The following represents the specifics of the present invention Examples, the present invention will be described in more detail. However, the present invention is not limited to this example. (Experimental Example 1) First, a polyester polyurethane resin is manufactured according to the following points. (Production of polyester polyurethane resin) A thermometer is provided. In the reaction vessel of the stirrer and part of the circulating cooler, add dimethyl terephthalate, dimethyl isophthalate, glycol, neopentyl glycol, zinc acetate, sodium acetate, The transesterification reaction was performed at 140 ° C ~ 220 ° C for 3 hours. The reaction system was decompressed to 20 minutes and 5 mmHg, and the temperature was increased to 250 ° C. The polycondensation reaction was performed at 0.1 mmHg and 25 ° C. After 60 minutes, polyesterdiol (1) was obtained Printed by the Consumer Cooperatives of the Central Bureau of Standards of the Ministry of Economic Affairs -------- installed! (Read the note on the back of the "Issue and then write this page") Alcohol = 5 0/5 0/5 0/5 0 (Mole ratio). Polyester diol (2) was obtained in the same way. Its composition is adipic acid / 1,4 butanediol / neopentyl glycol. = 1 0 0/7 5/2 5 (mole ratio) 〇 To a reaction vessel equipped with a thermometer, a stirrer and a circulation cooler, add toluene and methyl isobutyl ketone. The polyester diol (1 ), The second polyester paper size is applicable to Chinese National Standard (CNS) A4 specifications (210X297 mm> -15- printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs A 7 B7 V. Description of the invention 〇3) Alcohol (2) 4,4 > -Diphenylmethane diisocyanate, neopentyl glycol ', dibutyltin dilaurate, reacted at 70 ~ 90 ° C for 8 hours, and produced as shown in Table 1 Various polyester polyurethane resins having a number average molecular weight (Μη) and glass transition temperature (Tg). Then, a coating for forming a honing layer is prepared according to the following points. ≪ Coating for forming a honing layer > (1) Adhesion Agent Mixture) of the solution was adjusted

• Phenoxy resin + (PKHH number average molecular weight manufactured by Phenoxy Associates = 15 0 0 0) ......... 20 parts by weight • Polyester polyurethane resin (with the number average molecular weight shown in Table 1) Physical properties of Μη and glass transition temperature T g) ..... 8 0 parts by weight. Μ EK (butanone) ... 1 3 0 parts by weight ... toluene ... 1 3 0 parts by weight Parts • Cyclohexanone ... 140 parts by weight of this composition is put into an ultra-high mixing device, mixed and stirred for 6 hours to prepare an adhesive solution. This binding solution was cut with 95% shearing filtration accuracy = 15.0. After using the depth filter, it was subjected to 8-hour cycle filtration. (2) Dispersion treatment • Inorganic powder (Oxide Ming, manufactured by Fujuincopoleted) WA # 4 0 0 0) ......... 5 0 0 parts by weight • Adhesive solution (described above) ......... 5 0 0 parts by weight This paper is applicable to China National Standard (CNS) A4 Specification (210X297mm) -16 · (Please read the precautions on the back before filling this page)

* 1T Printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs A 7 __B7_ V. Description of the invention (14) After putting the combination into the grinder, it was dispersed for 3 hours. (3) Viscosity adjustment After the dispersing treatment is completed, the following solvent is added, and dispersing is performed for 1 hour. .Μ EK (Butanone ......... 7 0 parts by weight • Toluene ......... 70 parts by weight • Cyclohexanone ......... 8 weight The coating for forming the honing layer after adjusting the viscosity was subjected to 8-hour cycle filtration using a depth filter with a 95% shear filtration accuracy = 2 5 · 0 / zm. (4) The final coating was filtered after the coating 12 20 parts by weight was added an isocyanate compound (ColonateL, manufactured by Japan Polyurethane Industry Co., Ltd.). After 20 parts by weight, the mixture was stirred and mixed to form a coating for forming a honing layer. (Made by honing belt ·) at 7 5; m The honing layer-forming coating is coated on one side of a flexible support composed of a thick polyethylene terephthalate film and then dried. The dried honing layer has a film thickness of 15 and the coating is completed. The dried rolls were heated at 60 ° C. The ovens were hardened for 24 hours, and then cut into 3/4 inch widths to make honing belt test pieces. Various honing belt tests were made as shown in Table 1 below. After the product is finished, the paper size of each honing belt sample applies to the Chinese National Standard (CNS) A4 specification (210X297 mm) -17-(Please read the note on the back ^-matter master before filling this page)

A7 A7 ........ • Intact 0 ··· _ · • Have 1 ~ 2 scars, which can reach the level of the product. Δ ........ • It has 3 ~ 5 scars, which is a good standard for products. X ........ • With 6 or more scars, as a product with a secondary level. Printed by the Consumer Cooperatives of the Central Bureau of Standards of the Ministry of Economic Affairs —______ B7__ V. Description of the Invention (| 5) & The characteristics of relative honing energy, magnetic head honing damage, and honing belt scratching were measured according to the following points. Relative Honing Energy After honing a pure-grain ferromagnetic head using a honing belt sample, find the time required to honing the pure-grain ferromagnetic head 1 // m. This honing time is shown relative to the honing time of N 0. Sample 1. That is, the relative honing made when the honing energy of the reference sample N 0.1 is 100. Those who are less than 1,000 have better honing ability. To head honing abrasion After grinding pure grain iron with a honing belt sample, observe the damage state formed on the surface of the magnetic head with an optical microscope, and use the following as a criterion for judgment. Honing belt scratches When honing the pure grain iron with a honing belt sample, observe whether the honing layer of the honing belt is scratched with an optical microscope, and evaluate it with the following criteria. 〇 ......... No scratches appear. △ ......... has a slight scratch and reaches the product level. This paper size applies to Chinese national standards (CNS > A4 size (2 丨 0X297mm) — ~-1R-{Please read the notes on the back before filling this page}

A7 B7 V. Description of the invention (16) X ......... has obvious scratches and is a secondary product. The above measurement results are shown in Table 1 below. (Please read the notes on the back before filling in this page.) Ordered by the Central Standards Bureau of the Ministry of Economic Affairs and printed by the Consumer Cooperatives. This paper applies the Chinese National Standard (CNS) Α4 specification (210X297 mm) -19-Central Ministry of Economic Affairs Printed by Standards Bureau Consumer Cooperatives 396087 A7 B7 V. Description of Invention (/ ;?) Table 1

Sample No. Polyester polyurethane phenoxy / polyester relative. Magnetic head honing belt Μη Tg (° C) Polyurethane honing can abrasion scratches (weight ratio) 1 49000 -30 20/80 100 ◎ 〇2 25000- 30 20/80 99 ◎ 〇3 70000 -30 20/80, 101 ◎ 〇4 90000 -30 20/80 105 〇5 (comparative) 10000 '-30 20/80 140 ◎ X 6 (comparative) 150000 -30 20 / 80 120 X 〇7 49000 -45 20/80 110 ◎ 〇8 49000 20 20/80 98 ◎ 〇9 49000 40 20/80 95 〇〇10 49000 70 20/80 88 Δ 〇11 49000 -30 5/95 110 ◎ △ 12 49000 -30 10/90 106 ◎ 〇13 49000 -30 40/60 97 ◎ 〇14 49000 -30 50/50 90 ◎ 〇15 49000 -30 60/40 88 〇〇16 49000 -30 70/30 80 △ 〇17 (comparative) 49000 -30 20/80 120 ◎ X Sample No. 17: Sample No. The phenoxy resin is replaced by epoxy resin (M η = 6000) I -------- ί Installation-U · (Read the first read, please read the notes on the back, then fill out this page) This paper size applies to China National Standard (CNS) Α4 size (210X297 mm) 396087 A7 B7 Printed by the Consumers' Cooperative of the Central Standards Bureau of the Ministry of Economy Five 2. Description of the invention (18) (Experimental Example 2) / The honing belts 1, 5, and 6 were used in the above experimental examples. After the spare time, after honing the flexible disc, the damage and honing of the surface of the disc were evaluated. The results after scratching are shown in Table 2 below. Magnetic disk honing damage 硏 After bending a flexible magnetic disk with a honing belt, observe the damage formed on the surface of the magnetic disk with an optical microscope, and evaluate it with the following criteria. '〇 ...... determined without defect X ......... wounds generated, honing belt scratches for secondary products, after using the honing belt Sample for honing the flexible magnetic disc With an optical microscope, observe whether the honing layer on the honing belt has scratches. The following are the evaluation criteria. ○ ... No scratches occurred X ......... Scratches appeared, which is a secondary product. The measurement results are shown in Table 2 below. (Please read the notes on the back before filling #? This page) *-° This paper size applies to China & House Standard (CNS) A4 specification (210X297 mm) 21 _ A7 B7 396087 V. Description of the invention (> 9 ) Table 2

Sample Surface of magnetic discs Abrasion Abrasive tape Scratch 1 〇 〇 5 (comparative) 〇 X 6 (comparative) X 〇 The above results can clearly prove the effect of the present invention. That is, if the honing belt of the present invention is a honing belt with a honing layer containing inorganic powder and a binder as main components on a flexible support, the binding agent contained in the honing layer is composed of 1) benzene Oxy resin with

2) A polyester polyurethane resin with a number average molecular weight Mη of 2 OOOOSMnS 1 0 0 0 0 0, so it can effectively prevent honing damage on the surface of the object to be honed (honed object) and reduce the honing of the honing belt Layer scratches, and at the same time, have excellent honing ability and other effects were found.

In I In —.K n In HI ^ H--n HI n) 1 ^ 11 One OJ J '(Please read the notes on the back before filling out this page) Printed by the Staff Consumer Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs Paper size applies to China National Standard (CNS) A4 (210X297 mm) .22

Claims (1)

396087 A8 B8 C8 D8 VI. Patent application scope 1 type of honing belt, which is characterized in that the flexible support has a honing layer containing inorganic powder and a binder as the main component of the honing belt. The binder contained in the honing layer is composed of 1) a phenoxy resin and a polyester polyurethane resin having a number average molecular weight Mn of 2 0 OSMn S 1 0 0 0 0 0. 2. The honing belt according to item 1 of the scope of the patent application, wherein the number average molecular weight of the phenoxy resin is a composition having a number greater than 100%. 3. The honing belt according to item 1 of the scope of patent application, wherein the number average molecular weight of the phenoxy resin is more than 10,000 to less than 30,000. 4. The honing belt according to item 1 of the patent application range, wherein the weight ratio of the phenoxy resin to the polyester polyurethane resin is 5: 9 5 to 70: 30. 5. As for the honing belt of item 1 in the scope of patent application, in which the glass transition temperature T g of the polyurethane resin is -50 ° C ~ 80 ° C. Abrasive belt 'wherein the inorganic powder has a Mohs hardness of 5 or more and a particle size of 0.1 to 20 / zm. (Please read the precautions on the back before filling in the tiles.) Binding and printing. Printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs. This paper size applies to Chinese national standards (CNS > A4 size (210X297 mm) -23-